Nigerian scam comes in many forms: 419 scam, when they offer to transfer millions of dollars into your bank account, or lottery scam, when they tell you that you've won something in some bogus lottery.However, Nigerian dating scam (or romance scam), besides just asking for money for their studies, sick relatives, etc..They will send you the Money Orders or checks and ask you to deposit them into your bank account and then wire the money to them via Western Union.
If you cash them or deposit them into your account, Money Orders or checks will come back after few weeks as fraudulent and you will be responsible for paying back the money to the bank and sometimes even charged for passing counterfeit instrument.
Never re-ship anything for strangers, especially to Africa.
There is also a re-shipping scam, when they will ask you to re-ship goods for them.
These goods are purchased with stolen credit cards.
Recently there are also Nigerian scams originating from Malaysia, China, India, Turkey, Spain, Cyprus, Egypt, as that's where Nigerians are located since they can easily get to these countries without visas or on the student visas.
Men are usually widowed engineers, building contractors, military, vet doctors, surgeons or antique dealers.